News

Home > News > SJTU Zhang Hepeng’s Research Group Discovered New Model for Bacterial Collective Motion

SJTU Zhang Hepeng’s Research Group Discovered New Model for Bacterial Collective Motion

December 29, 2018      Author: Zhang hepeng

Recently, Zhang Hepeng's research group and its collaborators conducted a systematic research on the topological defects and collective motion of bacterial colonies using experimental, theoretical and numerical methods. Zhang's group is from School of Physics and Astronomy and Institute of Natural Sciences of SJTU. The research results were published online on December 28th in the Proceedings of the National Academy of Sciences with the title "Data-driven quantitative modeling of bacterial active nematics".

20180103

This work was mainly completed by Li He, a Ph.D. student of SJTU, Shi Xiaqing, Suzhou University, and Hugues Chate, Commissariat à l'énergie Atomique (CEA) offered theoretical guidance. Liu Chenli, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences, provided assistance in bacterial gene manipulation. The research work was funded by the National Natural Science Foundation, Shanghai Science and Technology Committee and Shanghai Municipal Education Commission.

Abstract: Active matter comprises individual units that convert energy into mechanical motion. In many examples, such as bacterial systems and biofilament assays, constituent units are elongated and can give rise to local nematic orientational order. Such "active nematics" systems have attracted much attention from both theorists and experimentalists. However, despite intense research efforts, data-driven quantitative modeling has not been achieved, a situation mainly due to the lack of systematic experimental data and to the large number of parameters of current models. Here, we introduce an active nematics system made of swarming filamentous bacteria. We simultaneously measure orientation and velocity fields and show that the complex spatiotemporal dynamics of our system can be quantitatively reproduced by a type of microscopic model for active suspensions whose important parameters are all estimated from comprehensive experimental data. This provides unprecedented access to key effective parameters and mechanisms governing active nematics. Our approach is applicable to different types of dense suspensions and shows a path toward more quantitative active matter research.

 

Translated by Zhu Fengyan    Reviewed by Wang Bingyu